Field of the Invention
The present invention relates to a Hall sensor.
Description of the Background Art
Vertical Hall sensors are known from the European patent application EP 9 540 85, which corresponds to U.S. Pat. No. 6,542,068, as well as from DE 101 50 955 C1, in which multiple electrically conductive regions extend perpendicularly to the surface of a substrate and into the substrate for the purpose of forming multiple Hall elements and which have multiple connecting regions of a side face on the surface of the substrate. Hall sensors are used in many technical areas, e.g., to detect the position of switches or actuators contactlessly and thus free of wear. In this area, the use and spatial detection of magnetic fields offer advantages over an optical or mechanical detection, since technologies based on magnetic fields, like those used in Hall sensors, are much less sensitive to contaminants than are optical methods.
A Hall sensor is known from DE 10 2011 107 767 A1, which corresponds to US 20130015853, which is incorporated herein by reference, and which shows four series-connected Hall elements, which are particularly suitable for reducing influences of offset voltages with the aid of the spinning current method.
In connection with lateral Hall sensors for suppressing the offset of the sensor signal, the spinning current method is known from the book titled “Rotary Switch and Current Monitor by Hall-Based Microsystems” by the author Ralph Steiner Vanha, Verlag Physical Electronics Laboratory, Swiss Federal Institute of Technology (ETH) Zürich, 1999, pages 39-53. In the spinning current method, the measurement and current directions at the Hall sensor are continuously further rotated in cycles by, for example, 90° at a certain clock frequency and summed up over all measuring signals of a full rotation by 360°, thereby reducing the influence of offset voltages.
A series arrangement of Hall element having three terminal contacts is furthermore known from EP 2049910 B1, which corresponds to U.S. Pat. No. 9,024,622, which illustrates two Hall elements being connected in parallel in each case. To carry out a calibration, a wire through which current flows is guided over the Hall elements.